1. Field of the Invention
This invention relates to pre-sweetened sugar-coated breakfast cereals and, more particularly, to the recovery of sugar from broken pieces of sugar-coated cereal that have fallen off or broken off the cereal product during production.
2. Description of Prior Art
Cereal pieces are typically prepared by cooking a cereal dough, shaping the dough into pellets or flakes and puffing or toasting the shaped dough. Pre-sweetened breakfast cereals have been regularly available to the consumer for several years. Such cereals have been prepared by first producing unsweetened cereal pieces, coating the cereal pieces with a sucrose slurry and drying the coated pieces in a dryer.
One approach for preparing breakfast cereal flakes is disclosed in U.S. Pat. No. 1,161,323. A grain such as corn grits is combined with salt, cane sugar and water. The combination is heated in a steam-tight cooker thereby cooking the grain material. The cooked grains are partially dried and then passed between spaced smooth-surfaced flaking rolls. The resulting flakes are puffed by baking or roasting. In other instances whole kernels of grain have been puffed to provide a breakfast cereal. U.S. Pat. No. 1,266,448 shows such a process in which rice kernels are soaked in water for 36 hours. The kernels are then subjected to heat until the kernel surface is dried. The dried kernels are popped in a popper much like popcorn.
A further process for preparing ready-to-eat breakfast cereals is described in U.S. Pat. No. 3,453,115. Cereal dough is prepared from any of various cereals such as corn, wheat, barley and oats. The dough is pressure cooked and pelletized. The pellets are partially dried to provide case hardening and then flaked between rolls.
The various ready-to-eat breakfast cereals have been sweetened by coating the finished cereal pieces with sugar. The previous unsweetened cereals have the disadvantage that table sugar, which is added to the cereal and milk mixture at the time of eating, is added in excess and remains in the bottom of the cereal bowl after the cereal has been consumed. The pre-sweetened cereals overcome such disadvantage and provide an appropriate amount of sugar which is not wasted.
U.S. Pat. No. 2,196,395 describes a process for candy-coating cereal in which the cereal is mixed with a hot sugar solution containing a fat or oil. The sugar solution can be in the form of molasses, glucose or cane sugar. The process is designed to permit the sugar-coating of relatively fragile cereal products, such as flakes, which may be damaged by other coating techniques, and is also stated to give the product good storage stability.
U.S. Pat. No. 2,333,442 describes the coating of a puffed cereal product with a honey-flavored candy coating. The coating is produced by contacting the cereal product with a hot solution containing sugar, honey flavoring and hardening agents. Following coating, the coated cereal is cooled to produce separation of the individual grains of sugar. It is stated that the process produces a hard coating which maintains its integrity and texture for long periods of time.
U.S. Pat. No. 4,211,800 d1scloses a flaked cereal product coated with sugar and oil to enhance both sweetness and storage stability. This process discloses a cereal flake in which the grain is either corn, wheat, or oats. The grain is first cooked and then dried to below 20% moisture. After tempering, the grains are heated to a temperature between 140.degree. F. and 200.degree. F. in order to produce a ppliable particle, The grains are then flaked, toasted, oil coated, and then sugar coated.
U.S. Pat. No. 3,615,676 discloses a sugar-coated ready-to-eat cereal. Sugar is applied to the surface of cereal pieces and caused to adhere thereto by moistening the cereal pieces with water and a binding agent.
U.S. Pat. No. 3,976,793 also shows sugar-coated ready-to-eat cereal flake. In this process, oat, soy & wheat flour are made into a dough. The dough is cooked, formed into pellets and then dried to a moisture content below 21%. The pellets are then flaked, toasted and sugar-coated.
All of the above sugar-coating processes have the disadvantage that a significant amount of sugar is lost due to breakage of the cereal. This breakage occurs whether the cereal is in the form of flakes, shreds, puffs or an extruded product. This breakage results in a high concentration of "dust" or "fines" which increases the cost of the final product. This is particularly true where the fines contain a high amount of sugar, say 65-90% sugar vs 10-35% cereal solids. Efforts to recycle the sugar-cereal fines into the pure sugar syrup which is used for coating the cereal have been limited since only small amounts (less than 6%) have been able to be added without deleteriously effecting the quality of the sugar coating. This is due to the presence of starch (from the cereal) in the recycled sugar.
Attempts to dissolve the sugar-cereal fines in water, and then separate the liquid sugar from the insoluble cereal (starch) particles by the use of filtration techniques has not worked due to plugging of the filters by the starches in the cereal and also by the mineral nutrients (zinc & iron) added to the cereal during production.
It would be very advantageous if the sugar fines could be dissolved, separated & purified to a point where more than 6% and as high as 20-30% of the reclaimed sugar could be recycled or added back to the original sugar syrup used for coating the cereal products.